The field of the present invention is air operated pumps.
U.S. Pat. Nos. 7,399,168; 7,063,516; 6,435,845; 6,357,723; 6,257,845; 5,957,670; 5,169,296; 4,247,264 disclose air driven and air controlled pumps. Various one-way valves for pumped medium are disclosed in these patents. Actuator valves used in such pumps are also disclosed in the foregoing and are specifically addressed in U.S. Pat. Nos. 7,125,229; 6,102,363; 4,549,467. The air valves for these pumps operate using a pilot valve system that senses pump position and initiates shifting of the pump through a directional control valve. U.S. Pat. No. 5,378,122 discloses an air driven pump which is controlled by a solenoid that times shifts independently of the position of the pump in its cycle. U.S. Pat. No. 7,517,199 discloses an air driven pump which is controlled by an electronic controller.